I have attached the pictures of the wiring harness.
This is the harness from the firewall through the alternator to the radiator (former voltage regulator) horn relay, low beam.

I don't know exactly where the white and blue wires go to the alternator. the two wires also go to the four way connector from the Voltage Regulator.

Maybe someone knows. I hope the pictures help.

If I don't need them, I'll clamp the alternator as described and try it out.

Translated with www.DeepL.com/Translator (free version)
Attachments
String to alternator.jpg (160.22 KB, 69 downloads)
Designation wiring harness.jpg (270 KB, 69 downloads)


1970 Chevrolet C10 Stepside and 1966 Chevrolet C60 Firetruck (Germany)